References

1. 1.AN857, Brushless DC Motor Control Made Easy (DS00857)
2. 2.AN1160, Sensorless BLDC Control with Back-EMF Filtering Using a Majority Function (DS01160)
3. 3.AVR444: Sensorless control of 3-phase brushless DC motors
4. 4.AN2522, Core Independent Brushless DC Fan Control Using CCL AVR® microcontrollers (DS00002522)